Shot-hole drilling apparatus



K. M. LAWRENCE ETI'AL 2,809,014

SHOT-HOLE DRILLING APPARATUS Oct. 8, 1957 '5 Sheets-Sheet 1 Filed Sept. 1-7, 1954 Ka /ya 11/. 1A wen/oz FINVENTORS.

0ct." 8, 1957 K. M. LAWRENCE ETAL ,809,0

SHOT-HOLE DRILLING APPARATUS 3 Sheets-Sheet 3 Filed Sept. 17, 1954 INVENTORS.

Unitiid States Patent-C snor-norn DRILLING APPARATUS Kenneth- M. Lawrence, Tulsa, Okla; and-Wesley K. Rickel, Qalgar'y, A1berta, Canada.; assignors to Geophysical Research Corporation, New York, N. Y., a corporation of'Ne'w Jersey Application-September 17, 1954, Serial No. 456,808

Claims. (Cl. 255- -35) The present invention relates to, shot hole drilling ap-' parat'us constituted by a powered rotary turntable" coupled to, an anger stem formed by a string of interconnected sections, and more particularly to an attachment adapted to facilitate the decoupling and removal of said stem sections upon completion of a boring operation;

In geological explorations for oil, it is conventional to, detonate a charge of powder, thereby causing waves to travel'dow'ninto' the earth. If these wavesimpinge upon a" rockstructure, such as a dome or other fault in whichthe normal position oftherocks is disturbed, the waves willibe reflected back to the surface. By measuring the distance the waves have travelledby means of a seismo'm'eter, thegeologist can locate certain structures, thereby obtaining clues as to where he may find oil. To create the explosion, it is the practice to drill a so-called shot-hole in which acharge of powder is placed.

In the conventional'shot-drilling rig, holes of different depths may be drilledby means of a multi-sectiondrill stem, the number ofsections used depending onthe desired depth of the hole. A bit is secured to the lowermost section of the'stem, and the stem is operated by means of a vertically-movable, powered rotary turntable. The relatively short stem sections are eachprovided at one end with an externally-threaded pin-or plug and at the other end with an internally-threaded:socket. Sections are joined together in end-to-end relation by inser'ting the plug of one section into the socket of the other. When boring a hole into the earths surface, as each sectionnpenetrates into the hole an additional section is coupled to the stemby first reversing the turntable to unscrew theassociated stem section-therefrom and then addihg a further section which is coupled into -engagement with the rig ,by operatingthe turntable in the drilling direction Thedifficulty experienced with drilling rigs of the above-described typeiarises when the hole is fully bored and it is desired to withdraw the stem therefrom and to dismantle thevarious sections. Heretofore, this dismantling operation could not be accomplished under power, for'in reversing the turntable-direction, the stem section-directly coupled to the turntable became uncoupled therefro'mp Hence, to separate an upper stem sectionfrom a lower stem section joined thereto, it was necessary to clamp the lower section to keep it from turning and then by manual means to unscrew the upper section to break the joint. As a consequence, the dismantling operation had to be performed manually and without the assistance of turntable power. With a string formed by a relatively largev plurality of stem sections, such dismantling operations entailed a considerable amount of time and effort.

Accordingly, it is the principal object of the present invention to provide a shot-hole drilling apparatus wherein decouplingas well as coupling of the stem sections is accomplished quickly and under'power.

More particularly, it isan object of the invention to 2,809,014 Patented Oct. 8, 1957 2 provide an attachment adaptedto facilitate the'decoupling of the stem sections, said attachment including dog elements engaging lugsformed on one end of each stem section.

Still another object of the invention is to provide an attachment of the above-described type having an inner coupling head for engaging, a drill stem section and an outer break-out sleeve axially slidable on said head, whereby said sleeve may be lowered to engage the lugs on the drill section coupled to the head.

Yet another object of the invention is to provide an attachment of the above-described type and including an inner head and an outer sleeve wherein the sleeve is axially slidable on the'head and wherein rotary 'movement of the sleeve relative to the head is prevented.

It is also anobjectof .the invention tov provide an improved drilling rig of sturdy and efiicient design.

For a better understanding of the invention as well as other and further objects thereof, reference is made to the following detailed description to be read in conjunction with the accompanying drawing .wherein like components are identified by like reference numerals.

In the drawing:

Fig. 1 is an elevational view of a shot-hole drilling ap-- paratus in accordance with. the invention.

Fig. 2 is an enlarged view, partially in section, taken:

ment for coupling the-turntable to the drill stem, the vattachment comprising aninner couplinghead and an outer break-out sleeve.

Fig. 4 is a top plan view solely of-the break-out sleeve: shown in Fig. 3.

Fig. 5 is a top plan View solely of the coupling head shown in Fig. 3.

Fig. 6 is a perspective view of the break-out sleeve.

Fig. 7 is an elevational viewof the coupling head.

Referring now to the drawings and more particularly to Fig. 1, the shot-hole drilling. rig in accordance with the invention comprises a vertically-movable crosshead or frame 10, a turntable. 11 rotatably supported in a horizontal plane within said frame, a multi-section drill stem 12 and an attachment 13 for operatively coupling said turntable to said drill stem.

Frame 10 includes a pair of parallel plates and is movable in the vertical direction along a pair of spaced columns 14, only one of which is shown in Fig. 1. A cable 15 is linked to the frame to raise or lower the positions thereof, as required. Turntable 11 is mounted on a hollow shaft 16 whose lower end projects below the frame. The turntable. is driven in either direction by a pinion 17 intermeshing with the turntable and coupled to a suitable power source such as an electrical motor. Drill stem 12 is constituted by astring of interconnected screw auger sections, three sections 12A, 12B and 12C being shown by way of example. Secured tothe extremity of the lowermost section- IZC is a suitable bit 18 having cutting edges for boring; a shot-hole in the earths surface 19.

As best seen in Fig. 2, each of the screw auger sections is provided with a spiral flight 19, which extends the, full length of the section, a tapered and externally-threaded plug 20 which projects from the lower extremity of .the section and a correspondingly tapered and internally-: threaded socket 21 formed in the upper extremity ofthe' section. In assembly, the plug 20 of one section isthreadably receivedwithin the socket 21 of the next section: Thus, inFig. 2, section 12A is joined to section 12Bin end-to-end relation.- The course of the thread is such thanin-rot-at ing.section. 12A" in thecloekwise or drilling direction the plug of this section turns into engagement with the socket 21 in section 12B. Consequently, in the drilling direction, the coupling between sections tends to tighten;" In order to unscrew adjacent sections, one of the sections -must be clamped against rotation, while the other section is turned in the counterclockwise or counter-drilling direction.

Extending longitudinally through each ofthe sections is a water passage 22,- the passages being interconnected when the sections are joined together. Bit 18 is provided with a'nozzle opening 23 which communicates with the water passage in the related stem section.

At the upper end of each section and extending laterally therefrom at diametrically-opposed positions are a pair of lugs 24 and 25 having a rectangular configuration. These lugs in conjunction withthe attachment 13 serve to facilitate the separation of thestem sections.

Attachment 13,- as best seen in Figs. 3-7, is comprised of an inner coupling head 26 and an outer break-out sleeve 27 concentric with said head and axially slideable thereon. The construction of the attachment is such that rotational movement of the sleeve relative to the head is prevented. Head 26 is formed by a cylindrical block whose upper end 28 is externally-threaded. As shown in Fig. 1, the upper end 28 of the head is received within a collar 29 secured to the free end of the turntable shaft 16, the end 28 of the head being fixedly held in the collar by means of a set screw 30.

The lower end 31 of head 26 is constricted in diameter to form a shoulder 32, and projecting from the lower end 31 is an externally-threaded coupling pin 33. Extending centrally through head 26 is a water passage 34, the upper portion 35 of said passage being enlarged to accommodate the end of a water pipe passing through the hollow shaft 16 of the turntable (Fig. 1). An 0 ring 37 is provided in the upper portion 35 to effect a watertight seal between pipe 36 and coupling head 26. Thus, water entering the attachment through pipe 36 flows through successive passages in the stem sections and is ejected from nozzle 23 in hit 18 attached to the lowermost section 12C.

Pin 33 of head 26 is threadably received within socket 21 in the upper stem section 12A, whereby rotation of the turntable 11 in the boring direction effects rotation of anger stem 12. Inserted in longitudinal grooves formed in coupling head 26 on diametrically-opposed sides thereof are rectangular bars 38 and 39, co-acting as keys for the break-out sleeve. On diametrically-opposed sides of the head at positions displaced 90 from keys 38 and 39 are concave recesses 40 and 41 adapted to accommodate friction catches. V

Break-out sleeve 27 is constituted by a hollow cylinder having a constricted portion 27A whose inner diameter is slightly greater than that of the outer diameter of head end portion 31, whereby the head telescopes within the sleeve. Formed in the sleeve 27 on diametrically-opposed sides thereof are longitudinal grooves 42 and 43 functioning as key-ways for the keys in the head, thereby permitting axial movement of the sleeve relative to the head but precluding rotational movement therebetween. Ex tending laterally from sleeve 27 is a circumferential flange 44 providing a safety surface and an operating handle.

A pair of releasable, frictional catches 45 and 46 are provided, each catch including a nipple 47 enclosed by a cap 48 and containing a spring 49 which urges a steel ball 50 into the associated recess into the coupling head. The lower end of the sleeve is triangularly notched at opposing sides of the sleeve to define a pair of dogs 51 and 52. When the break-out sleeve is urged downwardly by pressure applied to flange 44, the friction catches are re leased and the dogs 51 and 52 are brought into engagement with lugs 24 and 25 on the stern section joined to the coupling head. By rotating the turntable in the counter-drilling direction whereby the lugs on the upper section are engaged by the dogs on the attachment and clamping the adjacent section joined to the upper section against rotation, the upper stem section may be unscrewed from the lower section.

Referring now to Fig. 1 wherein the drill stem is constituted by sections 12A, 12B and 12C, the procedure will now be described by which the several sections are dismantled in coming out of the shot-hole. As will be seen in this figure, the upper section 12A is well above the earths surface, whereas the section 12B joined thereto is only partially withdrawn from the hole. The first step in the procedure is to hold section 12B with a wrench or a similar tool to keep it from turning and also from falling into the hole. Then, the break-out sleeve 27 on the attachment 13 is lowered to engage the dogs on section 12A. The direction of rotation of turntable 11 is reversed, thereby breaking the joint between sections 12A and 12B. After the joint is broken, the break-out sleeve on the attachment is raised. At this juncture, the wrench is applied to the lower end of section 12A to clamp same against rotation. The turntable is again operated in the reverse direction, thus breaking the joint between the coupling head 26 of the attachment and section 12A, and permitting the removal of section 12A from the stem. Now, by means of cable 15 the turntable is lowered to engage section 12B, and the turntable is rotated in the drilling direction so that the pin 33 on the coupling head 26 screws into the socket 21 in section 12B. The turntable is now elevated so that section 12B is lifted a few feet above the earths surface while section remains partially in the hole. Thereupon, the above-described steps are repeated, to permit the removal of section 12B. It will be seen from the foregoing that the several sections forming the drill stem may be removed under power, and the manual procedure heretofore entailed for this purpose is no longer necessary. It is to be understood that while the invention has been described in connection with shot-hole drilling apparatus, it is equally applicable to well-drilling and other forms of drilling rigs.

While there has been shown what is at present considered to be a preferred embodiment of the invention, it is manifest that various changes and modifications may be made therein without departing from the essential spirit of the invention. It is intended, therefore, in the annexed claims to cover all such changes and modifications as fall within the true scope of the invention.

We claim; I j

l. A shot-hole drilling apparatus comprising a vertically movable frame, a turntable rotatably mounted in said frame, power means coupled to said turntable selectively to effect rotation thereof in a drilling direction and in a counter-drilling direction, a drill stem constituted by a string of sections threadably joined in end-toend relation, each section having one lug at its upper end and an attachment for coupling said stem to said turntable, said attachment comprising a coupling head having a pin for threadably engaging the'uppermost section of said stem, and a break-out sleeve slidably mounted on said head and having a dog element for engaging said lug on said uppermost section, said sleeve including means to prevent rotation thereof relative to said head.

2. An attachment for coupling a powered turntable, rotatably mounted on a shaft terminating in a coupling collar, to a multi-section drill stem, said turntable being selectively rotatable in a drilling direction and in a counter-drilling direction, each section of which is provided at one end with an internally-threaded socket and a pair of oppositely-disposed lugs, said attachment comprising a cylindrical coupling head one end of which is externally-threaded for insertion in said collar, said head having a threaded pin projecting from the other end thereof for insertion in the socket of the uppermost sec-' tion of said drill stem, a break-out sleeve slideably mount ed on said head and having apair of dogs formed therein for engaging said lugs on said drill; section when said sleeve is axially lowered relative to said head, means to prevent rotation of said sleeve relative to said head, and releasable catch means normally to hold said sleeve on said head at a raised position thereon out of engagement with said lugs.

3. An attachment for coupling a powered turntable, rotatably mounted on a shaft terminating in a coupling collar, to a multi-section drill stern, each section of which is provided at one end with an internally-threaded socket and a pair of oppositely-disposed lugs, said turntable being selectively rotatable in a drilling direction and in a counter-drilling direction, said attachment comprising a cylindrical coupling head one end of which is externally threaded for insertion in said collar, said head having a threaded pin projecting from the other end thereof for insertion in the socket of the uppermost section of said drill stem, a break-out sleeve slideably mounted on said head and having a pair of dogs formed thereon for engaging said uppermost lugs on said drill section when said sleeve is axially lowered relative to said head, and releasable catch means normally to hold said sleeve on said head at a raised position thereon out of engagement with said lugs, said head further including a pair of diametrically-opposed keys operating within correspondingly positioned keyways formed in said sleeve whereby rotational movement of said sleeve relative to said head is prevented.

4. An attachment, as set forth in claim 3, further including an outwardly-extending flange formed circumferentially on said sleeve to provide a safety surface and operating handle.

5. A shot-hole drilling apparatus comprising a vertically reciprocable frame, a turntable rotatably mounted in said frame on a shaft terminating below said frame in a coupling collar, a pinion rotatably supported in said frame to drive said turntable selectively in a drilling direction and in a counter-drlling directon, a drill stern constituted by a string of sections threadably joined in end-to-end relation, each section having at one end there of a socket and a pair of oppositely-directed lugs and at the other end a threaded plug for insertion in the socket of another section, and an attachment for coupling said collar to said stem and including a cylindrical coupling head one end of which is externally threaded for insertion in said collar, said head having a threaded pin projecting from the other end thereof for insertion in the socket of the uppermost section of said drill stem, a breakout sleeve slideably mounted on said head and having a pair of dogs formed thereon for engaging said lugs on the uppermost drill section when said sleeve is axially lowered relative to said head, means to prevent rotation of said sleeve relative to said head, and releasable catch means normally to hold said sleeve on said head at a raised position thereon out of engagement with said lugs.

References Cited in the file of this patent UNITED STATES PATENTS 1,544,847 Mason July 7, 1925 1,714,818 Reed May 28, 1929 1,846,177 Bascom et a1. Feb. 23, 1932 2,181,641 Hicks Nov. 28, 1939 

